Beer experiment

I am about to begin an experiment in my microbiology course on the influence of yeast strain on volatile organic compounds in beer and I am in need of advise as I have never brewed before. I apologize in advance for asking so many questions, but if I mess up a batch I lose a bit of data. I plan on using a very light DME and of course I won't be using any hops. How much DME per gallon of water should I use? Should I use Di water or tap? Do I need beer specific container sanitizers or will a good rinse in bleach water followed by several rinses of boiling water do? I plan on doing fermentation in 1 gallon glass carboys (we have several old acid jugs), filled to approx 3/4 gallon, how much of a tube of liquid yeast is needed, Is there a danger of over pitching yeast.

I plan on using this as a learning experience and hope to save up some money to begin brewing my own beer. Thanks in advance for any response.

Diving head first aren't you, I'm also pretty new to this. It for the sanitizer question, some people say bleach is ok, others say it leaves off tastes. I just used iodine to sanitize my hydrometer the other day, star San or San star is a powder cleanser that I used to sanitize all my gear on brew day, it's a no rinse if youve never heard of it. Like 2.50$ a bag here in California. For the water, if you know exactly what is in the water then tap is fine if you plan on taking out some of the flavors, like the chlorine taste ect. Some people will get a water report and find out how much of what is in tap and they take a cleaner pill thing that removes some of the off taste stuff. Do you have a local brew shop near you? Because if you do he/she could help you out with the strain of yeast, how much, and help you with pitching information. As for pitching dangers I haven't heard of them, but that doesn't mean they aren't there. I hope this helps, I got a lot of my information from a "how to brew book" by John palmer(I think that's his name) and some friendly people on here have helped me with sanitizing questions,gravity questions, and just in general what to do's.

Happy brewing!

themdmc said:

I am about to begin an experiment in my microbiology course on the influence of yeast strain on volatile organic compounds in beer and I am in need of advise as I have never brewed before. I apologize in advance for asking so many questions, but if I mess up a batch I lose a bit of data. I plan on using a very light DME and of course I won't be using any hops. How much DME per gallon of water should I use? Should I use Di water or tap? Do I need beer specific container sanitizers or will a good rinse in bleach water followed by several rinses of boiling water do? I plan on doing fermentation in 1 gallon glass carboys (we have several old acid jugs), filled to approx 3/4 gallon, how much of a tube of liquid yeast is needed, Is there a danger of over pitching yeast.

I plan on using this as a learning experience and hope to save up some money to begin brewing my own beer. Thanks in advance for any response.

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To ur first query about dme I always use 5 to 6 lbs for fave gallons possibly less depending on what I'm brewing. Next I recommend some so u can drink that ish..I think ur solution would work but I suggest getting some starzan from lhbs..saves time more iffeciant and to the last I've found over pitching yeast never hurt anyone.. But if ur gonna go thru the trouble make a simple brew and drink ur homework..cheers and good luck

Because you are brewing from extract your tap water ought to be fine as long as it tastes good. Many people will still boil their water.
Bleach will work fine. Just makes certain it is very well rinsed.
3/4 lb of DME for 3 qts ought to give a low gravity beer. I got 1.044 OG from Briess pilsen light DME.
Hopville.com has a free beer calculator.
One tube of liquid yeast will be more than enough for 1 gal of beer (even stout beer).
I don't know of a "danger" to over pitching, but it may alter the taste. That I do not know.

Everything you need to know can be found in "how to brew" by Palmer...and it's free on line in short version, in an hour you'll be brewing your experiment!

3/4 lb should work well enough. I use would spring water or DI. If you are brewing for an experiment you probably don't care how it tastes anyway. Chlorine would be another variable you can do without. Camden tablets is what I believe you are referring to.

Bleach will work but there are food grade sanitizers you can use, Starsan is the most common.

You can over pitch but it is difficult to do. I would get white labs vials and just pitch one vial into each batch.

A question though, you are looking at the volatile compounds and you mentioned that you are not using hops. Hops would be the volatile organic compound in beer. Curious to hear more about your experiment. As I was a Bio major and a Microbiology TA in college.

Forget bleach it's more trouble than it's worth. Use Star-San....it's dirt cheap considering how much of it you get...and you can use it for a cleaner in the bathroom and kitchen even if you never brew again. With bleach you have to rinse it afterwards, and unless you're doing that with sterile water under controlled circumstances...it's just not worth it really. Very small chance that anything will get infected from your tap water or whatnot if you have to rise...but regardless of probable or not, it is possible. Why not spend a few extra bucks for the peace of mind.

Thanks for the help. I'll pick up some of that sanitizer. I'll be working in well equipped labs and could do my own water quality testing, but I think I'll go with tap just incase some of those ions are enzymatic cofactors. I'm not really worried about taste in general, just yeast strain ( secondary metabolites ) influence on flavor. As most flavors/aromas are volatile, I'll be using a GC/MS with a headspace sampler that I'll fabricate. Sure tons of flavor in the residual sugars and whatnot, but those were present in the wort to begin with. I'll make one large batch of wort, divide it into carboys and pitch different yeast into each, therefore any differences later is due solely to the yeast. Adding hops would make it drinkable, but only complicate analysis. That's the basic premise of the experiment. These metabolites are caused by enzymatic processes, which are the result of differences in genes and gene expression per strain.

There isnt a local home brew shop around, but I just set up a meeting with the head brewer at a local brewpub. As for yeast I have spoken with white labs, which confirmed my choices; Trappist, hefeweizen, burton, and a clean fermenting strain as a control. All ales for consistency so they can sit in the same location at the same temp.

By danger I ment to say non-ideal fermentation ie too fast thereby altering those secondary metabolites I'm interested in. Sorry, I was at work typing on my phone.

Nice I see where you're going with it now. Should be interesting........